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Hollow Cu/Fe3O4 heterodimer sub-microcactus has been successfully fabricated by a facile one-pot solvothermal method without any templates, which was confirmed by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectra (XPS) and a magnetic property measurement system. Batch experiments showed that the morphology is strongly influenced by the content of Cu in the Cu/Fe3O4 samples. A mechanism for the formation of the hollow heterodimer sub-microcactus by a cooperation of oriented attachment and localized Ostwald ripening processes has been proposed based on the observations of time-dependent experiments. Magnetic measurements illustrated that the prepared hollow heterodimer sub-microcactus are super-paramagnetic magnets with a saturation magnetization of 65.2 emu g-1. The synthesized hollow Cu/Fe3O4 heterodimer sub-microcactus may have important applications in catalysis, energy storage and biomedical applications. [ABSTRACT FROM AUTHOR]

Cubic phase NH4Eu3F10 nanospheres with controllable sizes were synthesized via a modified hydrothermal route by varying the dosage of ammonium hydroxide solution. Dependence of structure and morphology on the dosage of ammonia water and reaction time were investigated by X-ray powder diffraction (XRD) and transmission electron microscopy (TEM). Being unstable, NH4Eu3F10 decomposed into EuF3 and NH4F during the long-time hydrothermal treatment. EDTA, as the chelation agent of Eu3+ and the capping ligand on the surface of as-obtained nanospheres, showed different chelating abilities depending on the dosage of ammonium hydroxide solution. Increasing the amount of ammonia not only decreased the effective concentration of Eu3+, but also decelerated the growth of NH4Eu3F10 nanospheres and stabilized them by reducing the surface energy. Given the satisfactory hydrophilicity, biocompatibility, and luminescence, the as-obtained nanospheres were applied as promising agents for cell imaging by presenting high contrast. [ABSTRACT FROM AUTHOR]

Four different morphologies, including 1D nanobelts (1), 3D nanorod-flowers (2), fan-like (3) and rhombus-like (4) architectures have been synthesized from the mild reaction of Zn(Ac)2·2H2O and 2,2′-bipyridine-4,4′-dicarboxylic acid (H2L). The shape of the resulting coordination polymer particles (CPPs) was dependent on the amount of solvent and the molar ratio of reactants used in the reaction. In the experimental process, some additives such as triethylamine and acetic acid played a vital role in the formation of CPPs as means of adjusting the deprotonation rate of the organic linker (H2L), and thus affected the morphology of the resulting CPPs. We also investigated the effect of the different morphologies on the luminescent properties and bioactivities. [ABSTRACT FROM AUTHOR]

Four different morphologies of coordination polymer particles (CPPs) with identical structures, which have effects on their luminescent properties and antibacterial activities, have been synthesized. We accounted for the possible formation mechanisms of the different morphologies from the molecular level. The additives such as Et3N and acetic acid play an important role in the particle formation rate by means of manipulating the deprotonation rate of the organic linker and thus the particle size and shape. Meanwhile, in our future research work, we need to take the morphology effect into consideration. [ABSTRACT FROM AUTHOR]

A novel fluorescent sensor composed of a naphthalene functionalized tetraazamacrocycle ligand 3,6,9,15-tetraazabicyclo[9.3.1]pentadeca-1(15),11,13-triene-3-methyl naphthalene (1) and Zn2+has been designed and prepared, which can be utilized for selective and ratiometric sensing of pyrophosphate (PPi) over other phosphate-containing anions in aqueous solution at physiological pH. Notably, the water soluble 1itself also exhibits a selective enhanced fluorescent response to Zn2+, and the complex 1-Zn2+thus formed eventually fulfils the synergic Zn2+coordination-altered strategy with PPi. Furthermore, the ratiometric sensing of 1-Zn2+towards PPi performed well even in blood serum milieu. Finally, the sensor 1-Zn2+was successfully employed to monitor a real-time assay of inorganic pyrophosphatase (PPase) by means of ratiometric fluorescent measurements for the first time. [ABSTRACT FROM AUTHOR]

Single-crystalline SmF3sub-micropumpkins with a rattle-type structure have been successfully synthesized on a large scale by reaction of aqueous Sm3숫 ammonium fluoride in the presence of ethylenediaminetetraacetic acid (EDTA) at 110 °C for 16 h, which were confirmed by X-ray powder diffraction, energy dispersive X-ray analysis, transmission electron microscopy, and scanning electron microscopy. The reaction time and EDTA have been shown to play important roles in the formation of SmF3rattle-structured sub-microcrystals. A mechanism for the formation of the SmF3rattle-structured sub-micropumpkins viacooperation of an oriented aggregation process and Ostwald ripening has been proposed based on observations of time-dependent experiments. In addition, this crystal growth mode could be expanded to the synthesized Eu-doped SmF3rattle-structured sub-microcrystals. It is believed that the results of the present investigation may provide a versatile approach for designing and fabricating a wide range of nano/microcrystals. [ABSTRACT FROM AUTHOR]

Hexagonal phase EuF3hollow sub-microspheres and single-crystal hexagonal microdiscs with controllable sizes were fabricated viaa facile hydrothermal route at 110 °C for 8 and 14 h, respectively. Increasing the Eu(NO3)3concentration (from 0.125 to 0.2 M) increased the size of the microdiscs, but decreased the diameter of the sub-microspheres. Detailed investigations on samples at different preparation stages revealed that the hollow sub-microspheres were formed viaa self-transformation process within the same aggregated particles accompanied by the localized Ostwald ripening. Subsequently, hexagonal microdiscs were achieved at the consumption of the hollow sub-microspheres, which were attributed to oriented attachment mechanism. Moreover, the Ostwald ripening mechanism acted to form the secondary particles before the attachment. This kind of cooperation of two basic mechanisms may give us a new insight into the growth of EuF3microcrystals and opens a new way for controllable synthesis of other well-defined crystals in morphology and dimensionality. [ABSTRACT FROM AUTHOR]